Every written language has the scriptures in it today. What the translators do is find small tribes of a few hundred or so without a written language, invent a written language for them, translate the Bible into that language and then teach the small group how to read the language they just invented and then how to read the Bible.
What I have never understood is why its not better to teach an illiterate group to read a language far more widely written.
The reason we don’t translate into a national language is because it is a second language, and therefore less understood, than a mother tongue. There is a “clearing of a mist” type of revelation when a reader reads Scripture in the language they learned from birth.
A new alphabet isn’t always invented. Here in Indonesia, my colleagues use the alphabet used for the national language.
An example of the first topic however: my gardener started working for us when he left his village in the interior highlands here in Papua to finish his education at a national high school. In the meantime, the translation team in the highlands, which included his father, one of the head men of the village, worked at completing the New Testament. The gardener was literate in both the national languages and his village language. When the NT was completed and dedicated, the young man’s joy was unrestrained. It was “lebih terang”, more light, in his words.
I rejoiced, and am still rejoicing, that after almost 2000 years, he could read God’s Love Letter to him
One more example that might illustrate the reason better. If you speak a second language, try reading James 1 in that language. Then, read it in your mother tongue. Which one do you understand better? Which one rings a resounding bell in your heart? Unless you dream in that second language, my guess is that your mother tongue does the work for you.